Extant chairs in this style date no earlier than the Ming Dynasty (1368-1644), but apparently there is some artwork from as early as the 10th century depicting this chair form in China. The most popular era for these chairs was during the late Ming and early Qing dynasties (the Qing dynasty lasted from 1644-1911).
These chairs were often crafted out of huanghuali, which is part of the rosewood family, and was a favorite hardwood in traditional Chinese furniture. The wood itself is known as huali, while the modifier huang, or yellow-brown, refers to the patina of age.
During the Ming dynasty, a ban on maritime trade was lifted, making huanghuali and other hardwoods available. Although the basic form of the yoke-back chair had been established for centuries, this new hardwood material allowed craftsmen to reduce the chair to its most slender proportions. The unadorned simplicity of the chair was especially appealing to the elites during the late Ming era, and is an essential part of the Ming aesthetic.
Other than that evocative back rail, one of the key attributes of these yoke-back chairs is the design of the stretchers that support the legs. In antique Chinese designs, these stretchers are stepped up, so that one is higher than the other. The Chinese term for this is bubugao, which means "step higher" and originally referred to the promotion of an official. This association with status is not uncommon for chairs — in Western cultures, too, certain chairs were reserved for people who enjoyed a certain degree of authority or power.
A more visible attribute of the yoke-back chair is that wide center splat, the vertical back support between the seat and the crest rail. This was an innovation in chair designs; early Western chairs typically had a solid throne-like back. The center splat was occasionally carved or inlaid to decorative effect, but its original purpose was for function and comfort, because the user could sit with legs crossed beneath him (for this reason, the chair has occasionally also been known as a "meditation chair"). A pair of Chinese yoke-back chairs sent as a gift to King Phillip II in the 16th century must have been inspirational in the West; around a century later, those wide back splats, as well as similarly elegant proportions, appear in the Queen Anne (or Georgian) style chairs in England and America.
My main source for this post was Wang Shixiang, et al. Beyond the Screen: Chinese Furniture of the 16th and 17th Centuries. Boston: Museum of Fine Arts, 2000.
1 Kay Douglas interior, photo by Simon Upton for House Beautiful; 2 Sara Story Design; 3 Simon Upton for Elle Decor; 4 Michael S. Smith interior, photo by Grey Crawford for Elle Decor; 5 Amy and Todd Hase interior, photo by Roger Davies for Elle Decor. Originally published 10.21.10 - JL